Single Cell Profiling in the Sox10 ^Dom/+ Hirschsprung Mouse Implicates Hoxa6 in Enteric Neuron Lineage Allocation

Area of Science:

• Developmental biology
• Neuroscience
• Genetics

Background:

• Enteric nervous system (ENS) development is crucial for gastrointestinal motility.
• Sox10 deficiency causes aganglionosis, modeling Hirschsprung disease, and alters enteric neuron ratios.
• The precise impact of Sox10 on enteric neuron subtype ratios remains unclear.

Purpose of the Study:

• To investigate the effects of Sox10 deficiency on ENS progenitors and early differentiating neurons.
• To understand how Sox10 influences the diversification of enteric neuron subtypes.

Main Methods:

• Single-cell RNA sequencing (scRNA-seq) was performed on ENS progenitors and developing neurons from Sox10 mutant and wild-type littermates.
• scRNA-seq data was analyzed to identify cell-type markers, gene expression changes, cell fate trajectories, and gene regulatory network activity.
• Hybridization chain reaction (HCR) was used to validate scRNA-seq findings.

Main Results:

• scRNA-seq revealed three neuronal lineages from progenitors via two transition pathways with active Hox gene regulatory networks.
• Sox10 mutants showed a novel progenitor cluster, reduced transitional cells, and altered cell distributions.
• Hoxa6 expression was altered in neuronal lineages affected by Sox10 deficiency.

Conclusions:

• Sox10 mutation alters enteric neuron types by modifying neuronal trajectories during early ENS lineage segregation.
• Reduced neurogenic transcription factors, including multiple Hox genes, were observed in Sox10 mutants.
• This study implicates Hox genes in the lineage diversification of enteric neurons.